Just desktop background in preview

Running Ubuntu 10.04 in VBox 4.0.0 on a WinXP host shows a preview with just the desktop background and no windows or gnome panels.
During login, the preview of the login dialogue is shown, but once that is completed the new gnome panels and windows are not shown in the preview.
See the attached log for system info.

Same or similar problem: the preview freezes before desktop is shown. It was a small issue, however resources used to show the preview window are more and more used by the interface, like the screenshot image, the video capture and the mini toolbar background (see #12306). When the problem occurs, all these use the same still image.

This only happens when 3D acceleration is enabled; 3D has no visible issues

Some old OS like windowsXP and centOS 6.4 are OK with 3D enabled

With the same hardware, windows7 host is broken and ubuntu host is OK

In the attached logs, the windows7 guest is allways the same vdi. Fedora 17 has the problem and CentOS 6.4 does not.

update: ubuntu host is not ok, only the mini toolbar is ok because other method is used to draw it